Mesoporous carbon/Co composites with optimized impedance matching for enhanced microwave absorption and radar stealth performance

Composites of carbon and magnetic metals are attractive candidates for microwave absorbing materials (MAMs) due to their synergistic loss mechanisms and tailorable electromagnetic properties. In this work, magnetic Co nanoparticles were coupled with mesoporous carbon (MC) to enhance microwave absorption. Electromagnetic analysis reveals that Co nanoparticles fulfill dual functions: they introduce significant magnetic loss while moderately modulating the dielectric loss of the MC framework, thereby optimizing the impedance matching characteristics of the hybrid. Specifically, the MC/Co-2 sample achieves a minimum reflection loss of −37.55 dB at 9.24 GHz and a maximum effective absorption bandwidth of 3.3 GHz. The practical potential of the optimized sample is further validated by RCS simulations. Specifically, a maximum RCS reduction of 33.84 dB·m2 was achieved at a 0° incident angle, with an average RCS value of –22.8 dB·m2 across the entire detection range, demonstrating reliable radar stealth capability under simulated far-field conditions. This study not only provides a comprehensive evaluation of carbon/metal composites as potential MAMs, but also offers valuable insights into the synergistic mechanisms that guide the rational design of magnetic carbon-based absorbers for future stealth applications.